This is a set of items which can only be found in the Secret Cow Level. One special unique monster called the Cow King is created each time a portal is created to the Secret Cow Level, and killing him means the level can no longer be opened up by a character in that difficulty.

Cow King's Leathers is designed for a low level character. The items aren't geared toward any class in particular, but would be particularly useful for melee fighters with the GIAS full set bonus, as well as casting Static Field and Chain Lightning when being struck by monsters, something which Sorceress' and Necromancers wish to avoid. It is a pity that this set contains boots, otherwise it'd make a nice outfit for a Barbarian mercenary.

The items are named after parts of the Cow King's body, and this, along with the full set bonuses of extra gold and magic find probably make joking allusions to the greed of players who run this level.